Hydropneumatic scavenging pump regulator for deep boring equipments



Dec.27,1938. F. M. KOERVER 2,141,356

RYDRO NEUMATIC SCAVENGING PUMP REGULATOR FOR DEEP BORING EQUIPMENTS Filed March 30, 1937 2 Sheets-Sheet 1 Inventor Jliorney. v

Dec. 27, 1938. F. M. KOERVER 2,141,356 HYDROPNEUMATIC SCAVENGING PUMP REGULATQRFOR DEEP BORING EQUJIPMENTS Filed March-.30, 1937 2 Sheets-Sheet '2 v v Fig.2.

Inventor Attorney.

Patented Dec. 27, 1938 HYDROPNEUMATIO SCAVENGING PM REGUIATOR- FOR DEEP BORING EQUIP- MENTS Friedrich Wilhelm Koerver, Mulheim (Ruhr)-. Speldorf, Germany I! 55 M 937, Serial No. 183,783

In Germany 1 1936 '3Glaim8.

In deep boring equipments as usually einployed. a liquid is forced through the connected sections of the hollow drill stem for the purpose of clearing the hole being bored, the liquid being put 5 under a determined flushing by meansof a pressure pump. The pumps employed. for the purpose require to be adapted to pressures within 8r very wide range according to the depth to which the hole is bored, and thus the pump bodies are 10 usually provided with interchangeable bushes and plungers or other means provided to enable this requirement to be met.

When boringior oil a depth in the vertical bore hole,- for example, of 1500 metres or more is reached in the strata and the detritus resulting from the operation of the drill is scoured out of the bore hole by the flushing pump. In ordinary strata the pressure on the flushing liquid used is about 40 atmospheres, but if the drill happen to enter oil or gas bearing strata the pressure of the liquids and gases encountered may be greater than the pressure on the flushing liquid used. The danger is thus presented that the'counter pressure on the flushing liquid will rise considerably in a very short time. This sudden rise of pressure may also occur when for some reason or other such as by. caving-in of the wall of the bore hole the latter is choked. The sudden increase of pressure naturally endangers the pump and motor by reason of the sudden arrestment of movement of the moving masses of the motor and pump due to the high counterpressur'e.

According to the invention the pump and the 1 boring equipment have placed between-them a.

hydropneumatic air cushion by means of which heavy shocks can be taken up and at the same time certain controlling operations can be initiated by electrical means. A further object 3 40 of the invention is to avoid sudden overloading of the source of energy employed. For this purpose flasks filled with compressed air and' a flask usually called a liquid flask are used in the same manner as in electrically-controlled compressed air accumulators. The changing air pressure measured in the liquid flask or therising and falling level of liquid in this flask is used for controlling overflow valves and altemately starting and stopping lowpressure and"high pressure pumps.

As the liquid pressures in such 9. equipment change frequently it is advisable to use two pumps instead of one, so provided that when a particular admissible pressure is reached'for the first pump, .a second pump for a higher working pressure comes automatically into operation. This can be eiiected by one andthe same motor provided with couplings, butpump by-pass valves may instead be employed. Furthermore each pump may be driven separately and so-calied pressure 5 stage pumps may be employed. In the case of pressure stage pumps one or more low-pressure plungers are automatically disconnected, the high-pressure plungers being then at once put into operation. Furthermore in known manner l0.

reserve aggregates may be connected to the hydrd-pneumatic' control.

, The hydro-pneumatic switch gear may impart controlled impulses by mechanical means, by making use in the vessel itself or in a tube 15 specially provided for the purposecommunicating with the main vessel, of the vertically reciprocating movement of a float or piston for initiating the control movements.

' the floats can again be employed for electrical switch movements, so that the mechanical means represent only an intermediate part in the electrically controlled system. V

The inventionis illustrated in the accompany- 30 ing drawings. 1

Figure 1' illustrates a hydro-pneumatic control apparatus fitted with pump driving me hanism, which apparatus controls pumps and v ves by direct changes oi. air pressure in the apparatus. 35

Figure 2 illustrates a hydro-pneumatic control system which eiiects control by changes in the height of the liquids.

In Figure l, 1 represents the drill stem through which the flushing liquid is pumped; 2 is the well 40 head cover plate through which the flushing liquid may escape'through the gutter 3. 4 is the cation with theatmosphere through the outlet 50 pipe 8.

Located in the pipe 9, is a manually operable valve I0, whilst the pipe ll opens into apressure vessel I 2, connected beneath withthe pump l5 by way of a pipe 13, fitted with a manual valve ll.

The pipe between the valve I4 and the pump I5 is provided with a contact manometer l6 which on a predetermined pressure has been reached causes the actuation of. a lifting magnet I! on the auto- 5 matic stbp valve I8. The opening of the valve I8 efiects the opening of the pipe I9 which extends into the communicating pressure vessel 26. The pressure-vessels I2 and 20 are in communication at the upper part by way of a pipe 2I adapted to 10 be closed by means of a manually operable valve 22. The pressure vessel 20 is fitted with a contact manometer 23 by means of which the electromagnetic clutches 24 and 25 between the pumps I5 and 26 and the driving motor 29 can be brought into operation. The same contact manometer is also adapted to bring into operation the electrically controlled by-pass valve I. The pump 26 is in communication with the pipe I3 through the pipe 21 and the manually operable valve 28. The shaft of the electromotor 29 which is at one end adapted to drive the pump I5 through the clutch 24 and at the other the pump 26 through the clutch 25. 36 is a flask or air pressure vessel which is adapted to be connected up to the vessels I2 and 20 in order to increase the available volume of air.

The wiring between the contact manometer 23 and the electromagnetic clutches 24 and 25 and the electrically-controlled by-pass valve I is in- 30 dicated at 3|, while the wiring connecting the. contact manometer I6 with the magnet I'I is indicated at 32.

' The arrangement according to Figure 1 functions as follows:

In normal operation the stop valves Ill, I4 and 28 are open and the valve 22 is closed. The valve 1 is open between the pipes 6 and 9 and closed in respect of the outlet 8. The valve I8 is likewise in the open position so that the accumulators or vessels I2 and 20 are connected to the pump pressure conduit. When the flushing pressure is low, the coupling 24 is engaged and the coupling 25 disengaged. The low pressure pump I5 only is supplying liquid. Assoon as the flushing pressure rises to the highest permissible pressure for the low pressure pump, the contact manometer 23 which is responsive to and indicates the air pressure in-the vessel 20, releases the coupling 24 and at the same time engages the coupling 25, so that the low pressure pump is cut out and the high pressure pump supplies the liquid. If the flushing pressure rises to a value that is dangerous to the apparatus the contact manometer 23 reverses the valve 1. so that theaccumulators or vessels I2 and 20 are cut oil from the boring rod and the latter is placed in communication with the atmosphere by the outlet 8. Thus, a return of the flushing liquid to the vessel I2 and a dangerous increase of the flushing pressure are prevented. It the flushing pressure falls below a determined figure, the co act manometer I6 .tlosee the valve I 8 so that the vessel 20 with its large air system is shut oil from the pump pressureconduit. The result is that on'further falling 05 of the flushing pressure only the small quantity of air in the vessel I2 can pass tothe boring rod. The control and protectionoi" the plant thus follow automatically by reason 01' the air cushion in the vessels. Another typical embodiment of the invention is diagrammaticallyshown in Figure 2 inwhich the rotating drill stem is again indicated by I. the well head cover plate by 2, the discharge gutter for the flushing liquid'by 3 and the borlng'head by 4. a

7 The rigid pipe 8 is in communication wlth head 4 by a flexible pipe 5. This arrangement also is provided with the electrically controlled excess pressure valve I, which connects the pipe 6 with the pipe 9 and thus to the pressure vessel I0 communicating with the latter pipe and has an outlet 8 which opens to the atmosphere. The pressure vessel I0 is connected with the air vessel I2 by way of the pipe I I. The air flask or pressure vessel I2 in turn is connected through the pipe I3 with a vessel I4 partly filled with water and connected at the lower end with a. further vessel I6 by means of a pipe I5. Furthermore, the air spaces of the vessels I4 and I6 are connected by means of the pipe II. This connection may be interrupted by the hand-operated valve I8. The

vessel 1 6 is in communication with a switch device 20; the latter consists of two chambers 2| and 22 which are in communication one with the other.

Each of these two chambers contains a conducting liquid switch medium, advantageously mercury. The surface of the mercury in the chamber 2| is subjected to the pressure of the liquid in the vessel I6 by way of the pipe I9 provided with the hand-operated valve I9a, whilethe pressure of the air in the vessel I6 is applied to the surface of the mercury in the chamber 22 through the pipe 23 provided with a hand-operated valve 24. Dipping into the chamber 22 through the top cover are contact bars, by means of which bars electrical circuits can be made or broken by means of the mercury. These contact bars have leads 21 and 30 extending to the electromagnetic clutches 28 and 3| between the motor 33 and on the one hand the low pressure pump 29 and on the other hand the high pressure pump 32, and a lead 26 to the valve I,

The apparatus operates as follows:

Under normal workingconditions the valve I8 is closed, and the valve 1 connects together the pipes 9 and 6. When the flushing pressure is low the flushing liquid is supplied by the low pressure pump 29 driven by the motor 33 through the engaged clutch 28. When the flushing press ure rises the level of the liquid in the vessel I0 also rises. The effect is to lower the level of liquid in the vessel I4 and to raise it in the vessel I6.

. This change causes the mercury to rise in the chamber 22 and, as in the example shown in Figure 1, and through closure of the correspond,- ing circuits through thecontact bars, disconnects the low pressure pump from the motor when a determined pressure is attained and at the same time couples the high pressure pump large enough to accommodate the greater part of the flushing liquid from the boring rod or drill stem. By this means needless waste of flushing liquid is avoided and the transmission of gases or liquids from the well to the pumping or control systems through the yalve I can be reliably prevented. This security is afforded irrespective 7' action of the automatically controlled by-pass valve I is dependent upon the pressure oi the flushing liquid.

' I claim:

, ot the depth of the bore hole, inasmuch as the 1. In well boring equipments provided with means for the circulation of flushing liquid under pump pressure, a hydro-pneumatic control and safety system comprising a container for flushing liquid connected to the conduit extending between the pump equipment and the well boring equipment, the said liquid within the container being subjected to gas pressure, a two-way valve device connected to the said conduit between the container and the well boring equipment and adapted in one position to permit free flow through the 4 conduit and in another position to break the conduit and connect the well boring equipment to a discharge, and means responsive to the pressure of the flushing liquid in the circuit for controlling the operation of the pump'equipment and for setting the valve' device to break the conduit and open the discharge when the highest permissible pressure of the flushing liquid is exceeded.

2. In well boring equipments provided with means for the circulation of flushing liquid under pump pressure, a hydro-pneumatic control and safety system comprising a plurality of coupled containers connected to the conduit extending between the pump equipment and the well boring equipment and open to the said conduit to receive liquid therefrom, the liquid within at least one of the containers being subjected to gas pressure, a two-way valve device connected to the said conduit between the container and the well boring equipment and adapted in one position to permit free flow through the conduit and in another position to break the conduit and connect the well boring equipment to-a discharge, and controlling means responsive to the variations of level of the I liquid within the said container resulting from variations of the pressure of the flushing liquid in the circuit, the said means controlling the op? erati'on of the pump equipment and setting the valve device to break the conduit and open the discharge when the highestpermissible pressure of the flushing liquid is exceeded.

3. In well boring equipments provided with means for the circulation of flushing liquid under pump pressure, accordingto claim 1, th rovision of the container for flushing liquid of a capacity related to the circuit for flushing liquid in such manner that substantially the whole of the liquid contents of the circuit can be received into the container, and the provision of the control means to be eiiective to open the two-way valve device only after the container has been filled with flush- -ing liquid.

FRIEDRICH WILHELM KOERVER. 

